A Vibrant Seattle Through Transportation Excellence.

Keeping the Emerald City Green

Seattle wouldn’t be the Emerald City without all the beautiful trees that line our streets. Street trees provide shade and habitat, soften busy urban sidewalks, simply make our streets nicer places to spend time, and so much more.

So, who maintains the 40,000 “SDOT trees” spread along Seattle’s 1,675 linear miles of streets? SDOT’s team of nine arborists and a supervisor do this.

Seattle has about 250,000 street trees (all trees growing within public places are considered to be street trees; excluding trees in private yards, parks, etc.) that’s about a quarter of a million trees that need to be maintained.

Adjacent property owners are responsible for maintaining most of these street trees (when a street tree is planted, the property owner and the city agree who will maintain it), and SDOT maintains about 40,000 of them. Keep in mind that “SDOT trees” are more likely to be planted along busy arterials than on quiet neighborhood streets, so our arborists often work in very challenging environments.

Along busy Aurora Avenue N

Removing trees after a landslide on Highland Park Way SW.

SDOT arborists keep our street trees healthy, attractive, safe, and valuable. They prune about 5,000 trees per year so they’re not blocking people walking on sidewalks or vehicles driving down the street. They also deal with safety issues of street trees such as by assessing and removing the unstable ones.

Our team of arborists has special training so they can scale tall trees by climbing (sometimes more than 100 feet high) or by using aerial lifts and other heavy equipment. They also use traffic control skills on our busy streets and coordinate with agencies whose electric lines and trolley wires intermingle with tree branches. Most of the team are ISA Certified Arborists and hold Tree Risk Assessor qualifications. And of course, safety is always a top priority for the team.

SDOT arborists also provide emergency response 24/7 after a storm, car crash or a landslide, where they remove fallen or unstable trees, or branches from the scene.